Displays how a query would be executed, without executing it. The physical plan is the default, EXTENDED, CODEGEN, COST and FORMATTED change the output, and EXPLAIN CREATE MATERIALIZED VIEW tests whether a view can refresh incrementally.
Read more: Databricks docs
In the Ultra Transcenders books
Each book explains EXPLAIN in context, with comparison tables and the common traps.
Terms in this definition
- Physical
Describes the concrete, real-world parts that put a logical architecture into effect.
- CREATE MATERIALIZED VIEW
Used in SQL to declare this kind of view. Pipeline source files use a longer form,
CREATE OR REFRESH MATERIALIZED VIEW. - View
Shows a system through one chosen group of related concerns. No view is generic; each one is tied to whichever architecture it depicts.
Related terms
- ANSI
The American National Standards Institute, which made SQL a standard in 1986, a year before ISO did. Its standard types, for example INT, DECIMAL and VARCHAR, explain why SQL looks much the same from one vendor to another, even though each has its own dialect.
- Compute event logs
A history of lifecycle events on a compute resource, including its creation, termination and configuration changes. They explain why the compute changed rather than showing code output.
- Explain the increase
From a chart point's Analyze menu (line, bar or column charts), machine learning ranks the categories whose share moved most since the prior point; its twin, Explain the decrease, covers falls. RLS, DirectQuery and Top N filters all block it.